This study in north east Scotland has shown that Marfan syndrome has a minimal birth incidence of 1:9802 live births, a minimal prevalence of 1:14217, and that 8/30 (26.7%) of cases in our series are new mutations. The calculated mutation rate is 15 +/- 6.7 x 10(-6) and there is evidence of reduced reproductive fitness.

In some organisms longevity, growth, and developmental rate are improved when they are maintained on a light/dark cycle, the period of which "resonates" optimally with the period of the endogenous circadian clock. However, to our knowledge no studies have demonstrated that reproductive fitness per se is improved by resonance between the endogenous clock and the environmental cycle. We tested th...

Although there is presently no definitive evidence linking vaccinia virus transmission through reproductive cells, the Society for Assisted Reproductive Technology (SART) and the American Society for Reproductive Medicine (ASRM) accordingly recommend that assisted reproductive technology (ART) practitioners consider deferring individuals who are planning on donating gametes for reproductive use...

BACKGROUND Different reasons influence the current low birth-rate and the postponement of the birth of the first child throughout Europe. The aim of this study was to explore how highly educated women and men in Sweden reflect on fertility and postponed parenthood. METHODS We interviewed women (n = 22) and men (n = 18) who had started their professional careers and still had no children. Data...